Maternal and neonatal exposure to mercury in the Amazon: A systematic review

This systematic review investigated maternal and neonatal mercury (Hg) exposure in traditional Amazonian populations. Based on a comprehensive search of five databases (Science Direct, Scopus, Embase, PubMed, and Google Scholar), 13 observational studies (cohort and cross-sectional) published between 1998 and 2022 were selected and assessed using the National Heart, Lung, and Blood Institute (NHLBI) Quality Assessment Tool. The results showed transplacental and lactational transfer of Hg, demonstrating consistent positive associations between maternal and fetal contamination levels. However, the absence of significant impacts on growth or neurodevelopment suggests that the nutritional benefits of fish consumption may counteract the deleterious effects of Hg, or that social determinants exert a greater influence than chemical exposure itself. However, it is possible that social variables may have masked the toxicity of Hg in the methodologies used. These findings highlight the complexity of exposure in the region and the need for continuous monitoring of the mother-child dyad.